Heat exchangers and chromatography columns share several design objectives such as increased fluid-solid surface area, reduction of pressure drop requirements, and reduction of stagnant fluid flow. Chromatography is a technique for chemical separation of a fluid containing one or more chemical species. The fluid is transported through a structure where the fluid makes contact with an immobile phase such as a solid or a fluid-filled porous solid. Chemical species reversibly react with or are absorbed by the immobile phase to differing degrees, causing different chemical species to flow through the structure at different rates, thereby separating the species in the fluid.
Conventionally, chromatography has been conducted using packed-powder tubes containing powders that have reactive or sorbent features relative to one or more chemical species in an analyte fluid of interest. However, the need for high surface area for contact between the fluid and the packed powder in these conventional chromatography systems significantly impedes the flow of the fluid, requiring high pressures to maintain a desired flow rate. In heat exchangers, a thin, high-surface area solid is needed to separate two fluid phases, with similar flow considerations. Other applications with similar design considerations include catalyst columns, such as automotive catalytic converters; electrically resistive heaters; and filters, such as reverse osmosis filters for water desalination.